package demo07System;

public class Demo03 {
    public static void main(String[] args) {
        long l1 = System.currentTimeMillis();
        String str="";
        StringBuilder stringBuilder = new StringBuilder(str);
        for (int i = 0; i < 100000; i++) {
            StringBuilder append = stringBuilder.append(stringBuilder);
            System.out.println(append);
        }
        long l2 = System.currentTimeMillis();
        System.out.println("所需毫秒为:"+(l2-l1));
    }
}
